Inverter for sheet materials



June 27, 1933. c. E. IVES 1,915,672

INVERTER FOR SHEET MATERIALS Filed Sept-11, 1931 4 Sheets-Sheet 1 Q INVENT CUP/ 020 5 W55.

BY (P15 ATTORNEY June 27, 1933. c. E. IVES 1,915,672

INVERTER FOR SHEET MATERIALS Filed Sept. 11, 1931 4 Sheets-Sheet 2 mm mw v Q mm m W H 1. a N 6m (6m $3 Q 5 mi 1 I l I l l I l Ill E m 0 E M r M .M D m lilli- Q w 1 W F R QM F V m B uh June 27, 1933. Q E, IVES 1,915,672

INVERTER FOR SHEET MATERIALS Filed Sept. 11, 1931 4 Sheets-Sheet 5 INVENTOR' CL IF'F'OIPD E/VES' M5 ATTORN EY June 27, 1933. V CIHE. IV ES INVERTER FOR SHEET MATERIALS Filed Se a, 11. 1931 4 Sheets-Sheet 4 INVIENTOR CL/FFoeb E. I

ATTORNEY Patented June 27, 1933 r CLIFFORD E. IVES, OF WILMETTE, ILLINOIS, ASSIGNOR TO UNITED STATES GYPSUM COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS INVERTER .FOR SHEET 'MATIRIALS Application filed September 11, 1931. Serial No. 562,240.

This invention relates to methods of and apparatus for handling sheet material, and

has reference more particularly to methods and apparatus of the class described, especially adaptedto invert gypsum boards during their travel along a continuous conveyor. One of the developments in the art of manufacturing gypsum board is the production of a wallboard with one face surfaced with a white or ivory colored paper which is especially adapted for thereception of plastic paint without discoloring said paint, thus making it possible to use plastic paints having delicate shades and tints. It has been common practice to produce such wallboards or other gysum boards by passing said boards through kilns heated by direct firing in which the products of combustion come into direct contact with the gypsum boards. It sometimes happens that if combustion is not en tirelycomplete so that some soot or other dirt passes into the drying kiln, the rolls of the roller conveyors used for conveying the boards through the kiln, become dirty so that the light colored surface sheet becomes soiled upon passing through the kiln. Since this type of board isusuallymade with the white surface sheet turned downwardly, it becomes desirable to turn this board with the white sheet face up before passing same through the drying kiln or along any considerable distance of conveyor, so as to avoid soiling said light colored surface.

An object of this invention, therefore, is to provide a method and apparatus for inverting sheet materials as the pass along a conveyor on the way to a drying kiln.

Another object of the invention is to produee a board having an unsoiled surface sheet of light colored paper; also to improve gypsum boards and methods and apparatus for manufacture in other respects hereinafter specified and claimed.

Reference is to be had to the accompanying drawings forming a part of this specification, in which v Fig. 1 is a plan view of the inverting apparatus,

Fig. 2 is aside elevation of the inverting apparatus,

Fig. 3 is an end elevation of the apparatus with the construction,

Fig. 4 is a sectional elevation through the apparatus taken on line 4-4 of Fig. 1,

1 Fig. 5 is a sectionalv elevation through the apparatus taken on line 55 of Fig. 1,

Fig. Sis a sectional elevation through the apparatus taken on line 66 of Fig. 1,

Fig. 7 is-an elevation of the latch mechanism with parts broken away to disclose the construction, and

inverting Fig. 8 is a wiring diagram showing the electrical control means for the apparatus.

7 As constructed according to the present machine used by the gypsum board art, the gypsum boards 10 are composed of a core material composed mainly of hydrated gypsum which is surrounded on all sides by heavy paper cover sheets. The lowermost cover sheet has a surface paper layer which is ivory or white in color. These plasterboards or wallboards are formed by depositing the plastic core material between the paper cover sheets and allowing same to pass along a roller conveyor 11 until the setting of the core material is accomplished. This setting conveyor 11 is usually composed of rollers rotatably mounted in a suitable framework 12. The boards pass along the conveyor in the direction shown by arrow (Fig. 2.)

A board inverter 13 to be more fully described, is positioned in the path of travel of the boards 10 as they leave the conveyor 11, said inverter being arranged to receive the boards and turn them bodily over edgewise. After being turned over, the boards are automatically delivered from the inverter 13 onto a roller conveyor 14 which leads to the drying kiln where the boards are d led with their white face uppermost and t eir parts in section to disclose I dark face rest-ing upon the roller conveyors which convey said boards through the drying kiln. Both of the conveyors l1 and 14 extend at an angle to the horizontal so that gravity aids somewhat in moving the boards along said conveyors. However, the rolls of the conveyors 11 and 14 are usually power driven so as to cause the boards to move along said conveyors at a constant speed.

The inverter 13 made up of a plurality of longitudinal channel frame members 16 which are preferably four 'in number and spaced apart so as to lie parallel when seen in plan, as shown in Fig. 1, but said members are arranged in pairs, the pairs tapering outwardly from the conveyor 11 as seen in Fig. 2. Frame members 17 connect the longitudinal members 16 at the small end of the lnverter, and cross frame members 18 -connect the longitudinal frame members 16 at the large end of the inverter. Suitable cross connecting frame bars 19 connect the two pairs of longitudinal frame members 16, said bars 19 varying in lengths as the inverter increases in dimension. \Vherever possible, the frame members are preferably constructed of channels or bars and are connected together by welding. The entire inverter frame is pivotally mounted about. a central longitudinal axis which runs through a trunnion 21 (Fig. 6) at the small end of the inverter and a trunnion sleeve 22 (Fig. 4) at' the large end of the inverter. The trunnion 21 has an enlarged section 23 which is secured, preferably by welding, to a hollow beam 24 extending transversely of the inverter frame, said beam being secured at each end to the frame members 17. A ball race 25 is mounted securely upon the trunnion 21 and an outer race 26 is securely mounted, as by welding, to a transversely extending channel beam 27. Balls 28 are confined by the races 25 and 26 so as to permit the inverter to freely swin about its longitudinal axis under the contro of automatic mechanisms to be hereinafter described. A hook 30 is provided in the upper flange 31 of each end of the channel beam 27 and a cable 32 connects each of said hooks to a conventional chain hoist 33 which is secured to any suitable overhanging frame .work and is operated by the usual chain 34.

B means of the chain hoist, 33 the small end o the inverter can be elevated to different positions. relative to the roller conveyor 11 for a purpose to be hereinafter described.

Two separate conveyors are arranged within the frame of the inverter 13, these conveyors being arranged to convey the board in an upper receivin plane 36 and a lower discharge plane 3 these planes being spaced apart in angular relation such that the angle which each lane makes with the horizontal is substantia ly equal to the angle of inclinationaof the conveyors 11 and 14;, The inverter conveyors are composed of a plurality of upper shafts 39 and lower shafts 40, each of said shafts carrying a plurality of narrow rollers 41 and 42 respectively. Narrow belts 43 and 44 pass around the rollers 41 and 42 respectively, said belts passing around driven pulleys 45 and 45a at the large end Of the inverter, and around idler pulleys 46 at the small end of the inverter. The idler pulleys 46 are provided with adjustable take-up bean ings 48 for adjusting the tension of the belts 42", and 44.

The inner-reaches of belts 43 and 44 are resiliently spaced apart at substantiall the thickne s of the boards 10. The en s of shafts 39 are provided with ball bearings 50, which are mounted upon short longitudinal channels 51, the upper flanges 52 of which nest above the lower flanges 63 of the channels 16. Pins 54 extend upwardly through holes in the flanges of channels 16, and 51 (Fig. 5) ,a head 55 being formed on the upper end of said pins and a cotter pin 56 being provided on the lower end of the ins 54 for holding said pins 54 in position. pper compression spring 57 and lower compression spring 58 serve to urge the rollers 41 downwardly so as to exert a substantial pressure on the bo ards 10 and thus positively control their movement during the intermittent inovei'nent of the conveyor belts 43 and 44. The outer ends of shafts 40 are provided with ball bearings 60 which are mounted upon longitudinal angles 61 secured to longitudinal plates 109.

At the large end'of the inverter, a fixed frame-work is provided which includes a horizontally extending channel beam 63, supported by vertical standards 64. The'trunion sleeve 22 (see Fig. 4) passes through the web of channel beam 63 and is provided with a self aligning ball bearing 65 to provide substantially frictionless rocking of the inverter and to also permit the elevation of the small end of the inverter by chain hoist 33. The inner end of the trunnion sleeve 22 is provided with flange 67 and is secured to a hollow, built upbeam 68, a bushing 66 being preferably attached to said beam as by welding 69 and serving to support the outer end of sleeve 22. The ends of beam 68 are rigidly secured to the main framework of the inverter.

A .lever 70 has an integral collar 71 at one end which is secured to the outer end of the trunnion sleeve 22 by one or more keys 72. The outer end of lever 70 is bifurcated to form annular flanges 7 3 in which are mounted ball bearings 74. A pivot pin 75 is rotatably mounted in the ball bearings 74 transversely of the annular flanges 73. A connecting link 76 is loosely fitted between the legs 73 and tightly fitted upon the pin 75. Covering caps 77 serve to prevent dust and dirt from getting into the ball bearings 74. A

heavy spring 78 is secured to the outstanding end of connecting link 76 at one end, and at its other end. said spring is attached by a bolt 79 to a rigid bracket 80 secured to the supporting channel beam 63. Aided by the action of this spring 78, the entire inverter is caused to rock back and forth about its axis in a manner to be described.

The pulleys 45 and 45a are secured to shafts 82 and 83 respectively, and said shafts are provided on their outer ends with spur gears 84 and 85 respectively, of equal diameter to cause said shafts to move in opposite directions at the same speed. Each of the shafts 83 is provided near its center with a worm wheel 86. The two worm wheels 86 are on opposite sides and mesh with a worm 87, the latter being secured to the inner end of a shaft 88 which extends through the trunnion sleeve 22. The shaft 88 has a section 89 which is provided with a ball bearing 90 mounted within the annular trunnion sleeve flange 67. A similar ball bearing 91 supports the outer end of the shaft 88 within the integral collar 71 on lever 70. A dust cover 92 protects the ball bearing 91 from dust and annular splash plates 93 protect the ball bearing 90 from excessive lubrication. An oil case 94 is provided aroundthe worm wheels 86 and worm 87 so as to insure the proper lubrication of same. Glands 86a are used around shafts 83 on the oil case 94 to prevent leakage of grease past said shafts.

In order to cause the intermittent rota tion of the shaft 88 and actuation of the belts 43 and 44, I provide a pulley 95 secured on the outer end of shaft 88 by means of a key 96. An annular spacer 97 prevents end play and is used to separate the pulley 95 and ball bearing 91. The pulley 95 is preferably of a type provided with a plurality of annular Y- shaped grooves 98 for receiving a plurality of V-belts. A similar pulley 99 is provided on the end of a shaftlOO which is connected by flange 101 to a motor 102. The pulleys 95 and 99 are connected by driving V belts 9.9a. Magnetic brake 103 of conventional design is preferably also mounted upon the shaft 100 and its automatic electrical operation and that of the motor will be more fully described. The shaft 100 is mounted in suitable bearings 104.

The inverter 13 swings through a half circle of 180 and then swings back again through the same arc. Its swinging or rocking movements are controlled by a latch 106 engaging in a recess in a latch plate 107, the latter being formed on each of a pair of brackets 108 which are secured to opposite vertical frame bars 19, the latter being secured to the channels 16 of th'einverter frame (Fig. 7). The latch 106 has an enlarged body section 110 which is mounted for axial slid ing movement in an annular collar 111, the latter being secured to vertical standard 112 which is joined at the top by framemembers 113 to standard 114. The latch section 110 is also slidably mounted inthe 'vertic'al standard 114, and said latch section is provided 65 with a collar 115, a spring 116 being provided between said collar and the standard 114 for urging the latch 106 into engagement with the latch plate 107. The collar 115 is provided with an outstanding pin 117, upon which is rotatably mounted a square slide plate 118. Plate 118 is slidably mounted in a slot 119 formed in one arm of a bell crank lever 120 which is pivoted upon a pin 121 secured to the standard112. The other arm of the lever 120 islconnected by link 122 and pins 123 and 124 to the head 125 of a solenoid armature 126. A solenoid field 127 surrounds the armature 126for controlling the movement thereof and said solenoid field 127 is automatically controlled as will be more fully described. 7

An outstanding bracket 128 is secured to the inverter framework, and a rubber faced bracket 129 is secured to the standard '112 to be engaged by the bracket 128. A bracket 3 128 is attached to each side of the inverter 'frame so that said bracket 128 engages with the bracket 129 at the end of each 180 swing thus limiting the swinging of the inverter frame and accurately positioning the recess in the latch plate 107 opposite the latch 106.

A switch operating bracket 131 (Fig. 3') is secured to each side of the framework of the-inverter at about the horizontal centerline thereof said bracket having beveled outer faces 133 and 134 for cont-acting with rollers 135 and 136 of switch arms 137 and 138 respectively. The switch arms 137 and 158 are pivotally mounted on switch boxes 143 and 144 respectively.

A pair of switches and151 are movablv positioned upon the conveyor frame 12. These switches 150 and 151 have upstanding and downstanding legs 152 and 153 respectively, (Fig. 8). As a board '10 moves along 0 the conveyor 11, its leadingend presses the leg 152 and switch 150 outwardly against the action of aspring 154, thus serving-to open an electrical circuit 155. An instant later the leading end of the board also presses switch 151 downwardly against the action of a spring 156 pressing against the leg 153, thus tending to close the circuit 155. But the circuit has not been closed, because switch 150 is open.- When the rear end of the board goes past leg 152, the switch 150 momentarily closes the circuit 155, and when the rear end of the board 10 leaves the switch 151 an instant later, said circuit is again opened.

Solenoids 157, 158, 159 and 160 are provided in the electrical control circuit": Solenoids 1'57 and 158 actuate switches 161 and 162 respectively. Switches 163 and 164 are actuated by solenoid 159; and switches 165 and 166 'are actuated by solenoid 160. A main power line 168 delivers electrical current to switches 164 and 166 to actuate the motor 102, magnetic brake 103 and the latch m solenoid 127. A control line 169 is preferably used. to deliver current for actuating the solenoids 157, 158, 159 and 160. A manually actuated switch 170 is used in the main power line 168 and a manual switch 171 is used in the control line 169. For convenience in describing the automatic electrical operation of the various parts of the mechanism, I have listed the various circuits shown in Fig. 8 by the numerals 172 to 186. A push button manual switch 187 is provided in the circuit 174'to electrically close switches 163 and 164 thereby starting the motor 102 and putting the bolts 43 and/14 in motion.

In operation the board 10 passes along roller conveyor 11 and into position between the two belt conveyors 43 and 44; on the upper side of the. inverter 13. All the time that the board 10 is passing into the inverter, switches 163 and 164 are closed, due to passage of current through circuits172, 181, 180, and 177. lVhile switch 161 is closed, motor 102 is operating to move the conveyor belts 43 and 44 and the magnetic brake 103 is disconnected from shaft 100 to permit motor 102 to operate. The passage of the board orcrcmiveyor 11 tends to depress the switches 151 and 150 until the rear end of the board passes clear of the leg 152 of switch 150, which-allows said switch 150 to move upwardly under theaction of spring 154 and momentarily close the circuit 155. The clos- .mg of circuit- 155 actuated solenoid 158,

which throws switch 162, thus opening circuit 180 which in turn opens switches 163 and .164, stopping motor 102, and putting on the brake 103. The switch 162 being double-throw, closes circuit 186 which actuates solenoid 160 and closes switches 165 and 166. The closing of" switch 166 closes the circuit 185 and actuates the latch solenoid 127 so that the latch 106 is released from the latch plate-107, and spring 78 acts to start the rotation of the inverter about its trunnion 21 and trunnion sleeve 22. As the rear end of the board passes clear of the switch 151, circuit 155 is again broken, solenoid 158 releases the switch 162, but the latch solenoid 160 still remains in operation to keep the switches 166 and 165 closed, due to the. passage of current through circuits 172. 173. 178 and 182.

Since the upper conveyor of the inverter 13 contams acomparatively heavy plasterboard at the time the inverter starts to swing around under the action of spring 78, and the lower conveyor of the'inverter is empty, the weight of this board swinging thru the arc of 180 to the lower position, imparts sufiicient energy to overcome the resistances to rotation and will continue the swing of the inverter even though the spring 7 8 hangs loose during the middle of the swing of the inverter. However, as the inverter approaches the end the swing, the spring 78 again acts on the inverter to retard its speed and avoid undue hammering of the bracket 128 against the bracket 129.

At the end of the swing the bracket 131 strikes one of the when 135 or 136 to close the circuits 172, 174 and 177, which actuates solenoid 157 so as to actuate the switch 161. The actuation of switch 161 by solenoid 157 breaks the circuit including the solenoid 160 so that the latch 106 again engages the'latch plate 107 to hold the inverter in place while it is receiving and discharging the boards. The actuation of the switch 161 also closes the circuits 172, 173, 179, 180 and 177 thus actuating solenoid 159, and again causing the rotation of motor 102 and the release of magnetic brake 103 and causing the inverter to discharge this lower board and simultaneously receive another upper board. The actuation of switch 161 by solenoid 157 is only momentary, and the switch 161 again returns. After said switch 161 opens, the motor is kept running and switch 163 is kept closed owing to the fact that current passes along circuits 181, 180 and 177.

When it is desired to make gypsum boards of the plasterboard ty e which do not have white faces and there ore do not have to be inverted the chain hoists 33 are then used to elevate the small end of the inverter so that the lower conveyor on the inverter registers with the conveyor 11. The boards then pass straight through the inverter without being inverted. The inventor is prevented from inverting by rendering the switches 150 and 151 inoperable so that the motor 102 runs continuously.

1' would state in conclusion, that while the illustrated examples constitute a practical embodiment of my invention, I, do not wish to limit myself precisely to these details, since manifestly the same may be considerably varied without departing from the spirit of the invention as defined in the appended claims.

Having thus described my invention, I claim as new anddesire to secure by Letters Patent l 1. In an inverter for sheet material, a discharging conveyor, a receiving conveyor having its end spaced apart from the end of said discharging conveyor, a pivotally mounted conveyor positioned between said discharging and receiving conveyors, said pivoted conveyor being adapted to receive a board from said discharge conveyor, means for moving said pivoted conveyor about its pivot so as to of conveyors in spaced relation, means for' intermittently moving said conveyors, means for rotating said conveyors about a fixed axis, catch means for holding said conveyors stationary and preventing the pivotal movement thereof iand automatic means for releasing said catch when a sheet is deposited on one of said conveyors, so as to permit the inversion of said sheet.

5. In an inverter for sheet material, a con.- veyor for bodily pivotal movement, means for causing the intermittent, forward movement of said conveyor, means for pivotally moving said conveyor, means for depositing a sheet of material on said conveyor, so that said sheet is inverted during the pivotal movement of said conveyor, and conveying means for receiving said sheet after inverslon.

6. In an inverter for sheet material, a pair of conveyors in spaced relation, automatic catch means for maintaining said conveyors in a fixed position, means for charging and discharging sheets from said conveyors, the

weight of one of said sheets being adapted to cause the pivotal movement of both of said conveyors when said catch means is released, and spring means for starting .the pivotal movement of both of said conveyors.

7. In an inverter for sheet material, a conveyor frame, means for pivotally supporting said frame, a conveyor mounted upon said frame, a motor for causing the intermittent movement of said conveyor, automatic means operated by a sheet of material associated with said conveyor for starting and stopping said motor, and a magnetic brake associated with said motor for suddenly stopping said motor and said conveyor.

8. In an inverter for sheet material, a conveyor frame, a pair of conveyors mounted upon said conveyor frame, means for moving said conveyors, means for accomplishing the intermittent pivotal movement of said conveyors, conveyor means for discharging sheets of material onto the uppermost of said pair of conveyors, conveyor means for receiving sheets of material from the lowermost of said pair of conveyors, and means for elevating said frame so that the lowermost of said pair of conveyors registers with said discharging conveyor.

9. In an inverter for sheet material, a convveyor frame, conveyors mounted upon said frame and having a pair of belt reaches in spaced, opposed relation for the reception of a sheet of material therebetween, means for intermittently moving said conveyors, means for inverting said conveyor frame and said sheet of material, and means for resiliently pressing one of said conveyors toward the other said conveyor, so as to compress said sheet of material during inversion.

10. In an inverter for sheet material, a conveyor frame, a conveyor movably positioned upon said conveyor frame, means for causing the pivotal movement of said conveyor frame, power means for causing the-intermittent movement of said conveyor, switch means adjacent said conveyor frame, and means on said conveyor frame for actuating said switch means during the pivotal movement of said conveyor frame, so as to accomplish the starting and stopping of said power means. 11. In an inverter for sheet material, a conveyor for moving said sheet along a predetermined path, an inverter conveyor frame for receiving sheets of material from said conveyor, said frame being arranged to move pivotally to accomplish the inversion of said sheets, electrical means for accomplishing the inversion of said frame, and switch means associated with said conveyor 'andarranged to be actuated by said sheets during the movement thereof, so as to control said electrical means and the inversion of said frame.

CLIFFORD E. IVES, 

